Method and device for creating turbulence by pulsating flow

Patent metadata

Field	Value
Publication number	US-10449281-B2
Application number	US-201414902705-A
Country	US
Kind code	B2
Filing date	Jul 2, 2014
Priority date	Jul 2, 2013
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

A method and a device use pulsed flow profiles in the addition of a solution to an extracorporeal circulation to improve the mixing of the added solution with the blood, in particular in regional anticoagulation with citrate. Extracorporeal blood treatment processes are usually carried out with anticoagulation of the blood. In regional anticoagulation with citrate, sometimes a clot is observed in the extracorporeal blood circulation at the point of addition of the calcium infusion solution. If the extracorporeal circulation becomes occluded, the treatment must be interrupted. To prevent this, the method and device add the calcium infusion solution with a pulsed flow profile, with which better mixing is achieved.

First claim

What is claimed is:

1. A method of mixing blood with an infusion solution A in a T-section of a tubing system for an extracorporeal blood treatment, in which the blood, is pumped by a first pump in a main line of the tubing system, and the infusion solution A is pumped by a second pump out of a branch line through the T-section and into the main line, said method comprising:
controlling or regulating the second pump with a control unit such that the second pump runs discontinuously to pump the infusion solution A with a pulsed flow profile associated with a desired dosage thereof,
with the control unit calculating the pulsed flow profile for the second pump using a stored algorithm that accounts for a flow rate of the first pump,
such that based on an average flow rate (Vm) of the infusion solution A that is associated with the desired dosage, and on an optimal pulse flow rate (Vopt) that occurs in a peak of a pulse of the pulsed profile, which provides for enhanced mixing of the infusion solution A with the blood, the control unit determines a pulse width (Tau 2 ) and a pulse frequency (f) that will provide the enhanced mixing.

2. The method according to claim 1 , wherein the control unit controls or regulates the first pump such that the first pump runs continuously to pump the blood at a steady flow rate.

3. The method according to claim 1 , further comprising pumping an infusion solution B with a third pump out of an additional branch line and into the main line of the tubing system for the extracorporeal blood treatment.

4. The method according to claim 1 , wherein the extracorporeal blood treatment is performed using regional anticoagulation.

5. The method according to claim 3 , wherein the infusion solution A is an infusion solution containing calcium, and the infusion solution B is an anticoagulant solution containing citric acid.

6. The method according to claim 3 , wherein the control unit controls or regulates the third pump to pump the infusion solution B into the main line.

7. The method according to claim 3 , wherein the control unit calculates the pulsed flow profile for the second pump using the stored algorithm that takes into account the flow rate of the third pump.

8. The method according to claim 1 , wherein the pulsed flow profile is entered by a user on a user interface and is transmitted to the control unit.

9. The method according to claim 1 , wherein the extracorporeal blood treatment is hemodialysis, hemofiltration, and/or hemodiafiltration.

10. A device for extracorporeal blood treatment, said device comprising:
a first pump for pumping blood, a second pump for pumping an infusion solution A, and a control unit,
the control unit controlling or regulating the second pump such that the second pump runs discontinuously to pump the infusion solution A with a pulsed flow profile associated with a desired dosage thereof,
with the control unit calculating the pulsed flow profile for the second pump using a stored algorithm that accounts for a flow rate of the first pump,
such that based on an average flow rate (Vm) of the infusion solution A that is associated with the desired dosage, and on an optimal pulse flow rate (Vopt) that occurs in a peak of a pulse of the pulsed profile, which provides for enhanced mixing of the infusion solution A with the blood, the control unit determines a pulse width (Tau 2 ) and a pulse frequency (f) that will provide the enhanced mixing.

11. The device according to claim 10 , wherein the control unit controls or regulates the first pump such that the first pump runs continuously to pump the blood at a steady flow rate.

12. The device according to claim 10 , further comprising a third pump for pumping another infusion solution that is an anticoagulant.

13. The device according to claim 12 , wherein the control unit controls or regulates the third pump.

14. The device according to claim 12 , wherein the control unit calculates the pulsed flow profile for the second pump using the stored algorithm that takes into account the flow rate of the third pump.

15. The device according to claim 14 , further comprising a user interface for input of working parameters of at least one of the first pump, the second pump, and the third pump, with the user interface transmitting the working parameters to the control unit.

16. The device according to claim 10 , wherein the device is a dialysis machine.

17. The device according to claim 12 , wherein the anticoagulant is a citrate.

18. The device according to claim 16 , wherein the dialysis machine is a hemodialysis machine, a hemofiltration machine, and/or a hemodiafiltration machine.

Assignees

• Fresenius Medical Care Deutschland Gmbh

Inventors

• Peters Arne

Classifications

• A61M2205/3334

  Measuring or controlling the flow rate · CPC title

• A61M1/3672

  Means preventing coagulation · CPC title

• A61M2205/502

  User interfaces, e.g. screens or keyboards · CPC title

• A61M1/3458

  having electrolytes not present in the dialysate · CPC title

• A61M5/142

  Pressure infusion, e.g. using pumps · CPC title